Magnetic resonance imaging of esophageal squamous cell carcinoma using magnetite particles coated with anti-epidermal growth factor receptor antibody.
A highly specific and effective magnetic resonance imaging (MRI) contrast agent was prepared by coating super-paramagnetite particles with monoclonal antibodies (MAbs) directed against epidermal growth factor receptors (EGFRs), which are over-expressed in esophageal squamous cell carcinoma. The preparation maintained both the immunoreactivity of the MAbs and the full relaxing capability of the magnetite particles. The particles of this EGFR-specific contrast agent are 13.2 +/- 1.9 nm in size, and thus, it is assumed that they are smaller than capillary pores and, hence, able to escape scavenging by reticulo-endothelial system cells. The EGFR-specific T2-relaxing ability of this contrast agent was ascertained first in vitro, using the EGFR-expressing cell line TE8 and the EGFR-deficient cell line H69. The results in athymic rats bearing TE8 or H69 tumors revealed that the agent has EGFR-specific MRI contrast capacity in vivo. The electron-microscopic findings in TE8 tumor-bearing rats revealed that the magnetite particles had been taken up by their lysosomes. In conclusion, immuno-specific MRI using magnetite particles coated with MAbs against EGFR appears to be useful in the diagnosis of squamous cell carcinoma of the esophagus.
Suwa
T
T
Department of Surgery, School of Medicine, Keio University, Tokyo, Japan.
Ozawa
S
S
Ueda
M
M
Ando
N
N
Kitajima
M
M
D000818:Animals; D000911:Antibodies, Monoclonal; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis*; D066246:ErbB Receptors / Q000276:immunology*; D004938:Esophageal Neoplasms / Q000175:diagnosis*; D005260:Female; D052203:Ferrosoferric Oxide; D007158:Immunologic Techniques; D007501:Iron; D008247:Lysosomes / Q000378:metabolism; D008279:Magnetic Resonance Imaging / Q000379:methods*; D051379:Mice; D008807:Mice, Inbred BALB C; D010087:Oxides; D051381:Rats; D011923:Rats, Nude
D000911:Antibodies, Monoclonal; D010087:Oxides; D007501:Iron; D066246:ErbB Receptors; D052203:Ferrosoferric Oxide